Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

Fast parallel algorithms for short-range molecular dynamics

Modelling of fuel droplet heating and evaporation: Recent results and unsolved problems

Development of lanthanum strontium cobalt ferrite perovskite electrodes of solid oxide fuel cells – A review

Evaluation of the engine performance and exhaust emissions of biodiesel-bioethanol-diesel blends using kernel-based extreme learning machine

Supercapacitors are increasingly used for energy conversion and storage systems in sustainable nanotechnologies. Graphite is a conventional electrode utilized in Li-ion-based batteries, yet its specific capacitance of 372 mA h g−1 is not adequate for supercapacitor applications. Interest in supercapacitors is due to their high-energy capacity, storage for a shorter period and longer lifetime. This review compares the following materials used to fabricate supercapacitors: spinel ferrites, e.g., MFe2O4, MMoO4 and MCo2O4 where M denotes a transition metal ion; perovskite oxides; transition metals sulfides; carbon materials; and conducting polymers. The application window of perovskite can be controlled by cations in sublattice sites. Cations increase the specific capacitance because cations possess large orbital valence electrons which grow the oxygen vacancies. Electrodes made of transition metal sulfides, e.g., ZnCo2S4, display a high specific capacitance of 1269 F g−1, which is four times higher than those of transition metals oxides, e.g., Zn–Co ferrite, of 296 F g−1. This is explained by the low charge-transfer resistance and the high ion diffusion rate of transition metals sulfides. Composites made of magnetic oxides or transition metal sulfides with conducting polymers or carbon materials have the highest capacitance activity and cyclic stability. This is attributed to oxygen and sulfur active sites which foster electrolyte penetration during cycling, and, in turn, create new active sites.

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Advanced materials and technologies for supercapacitors used in energy conversion and storage: a review

Perovskite LaNiO3-δ oxide as an anion-intercalated pseudocapacitor electrode

Effects of injection timing on combustion and emissions in a diesel engine fueled with 2,5-dimethylfuran-diesel blends

Combustion performance and pollutant emissions analysis using diesel/gasoline/iso-butanol blends in a diesel engine

The content of oxygen vacancy, as the intercalation places of oxygen during the oxygen ion intercalation process, has a significant influence on the electrochemical properties of the perovskite pse...

Facile Synthesis of LaCoO3 with a High Oxygen Vacancy Concentration by the Plasma Etching Technique for High-Performance Oxygen Ion Intercalation Pseudocapacitors

Mingrui Wei

Papers

Perovskite LaNiO3-δ oxide as an anion-intercalated pseudocapacitor electrode

Effects of injection timing on combustion and emissions in a diesel engine fueled with 2,5-dimethylfuran-diesel blends

Combustion performance and pollutant emissions analysis using diesel/gasoline/iso-butanol blends in a diesel engine

Facile Synthesis of LaCoO3 with a High Oxygen Vacancy Concentration by the Plasma Etching Technique for High-Performance Oxygen Ion Intercalation Pseudocapacitors

Ruddlesden-Popper type La2NiO4+δ oxide coated by Ag nanoparticles as an outstanding anion intercalation cathode for hybrid supercapacitors